Background: The human cerebellum consists of two lobes and each cerebellar hemisphere consists of Gray and white matter. The gray matter has outermost layer called Molecular cell layer, the middle layer composed of Purkinje cell and innermost is Granular cell layer. In the Molecular layer are Stellate, Basket and Dendrites of Purkinje cells. The middle layer presented the characteristic pyramidal shaped Purkinje cells.

Aim: To evaluate and record morphological data of the thickness of purkinje cells layer in normal Control group A and in group B rodents which were given lithium carbonate so as to prove the lethal property of the anti-depressive drug lithium carbonate on the histology of Purinje cells layer of cerebellar cortex.

Method: Ten albino rats were given lithium carbonate for a period of six weeks and then micrometry was carried out for both groups.

Results: The data which was obtained in both groups was analyzed and it was concluded that the Clinicians and population should be aware of the deleterious effects of lithium carbonate.

Conclusion: Our study defined the consequences and the sequele of using Lithium carbonate by patients suffering from psychosis as Lithium can cause toxicity even at therapeutic doses.

Keywords: Micrometry, deleterious, rhombencephalon